Processing system and method for providing a heated etching solution

Abstract

A method and processing system are provided for independent temperature and hydration control for an etching solution used for treating a wafer in process chamber. The method includes circulating the etching solution in a circulation loop, maintaining the etching solution at a hydration setpoint by adding or removing water from the etching solution, maintaining the etching solution at a temperature setpoint that is below the boiling point of the etching solution in the circulation loop, and dispensing the etching solution into the process chamber for treating the wafer. In one embodiment, the dispensing includes dispensing the etching solution into a processing region proximate the wafer in the process chamber, introducing steam into an exterior region that is removed from the wafer in the process chamber, and treating the wafer with the etching solution and the steam.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]Pursuant to 37 C.F.R. §1.78(a)(4), this application claims the benefit of and priority to prior filed Provisional Application Ser. No. 61 / 801,072, filed Mar. 15, 2013; Provisional Application Ser. No. 61 / 924,838, filed Jan. 8, 2014; Provisional Application Ser. No. 61 / 924,847, filed Jan. 8, 2014; and Provisional Application Ser. No. 61 / 928,894, filed Jan. 17, 2014. The entire contents of these applications are expressly incorporated herein by reference.FIELD OF INVENTION[0002]The present invention relates to the field of providing a heated etching solution to a process chamber where it is used to treat a wafer, and more particularly to a processing system and method for improving temperature and water content (hydration level) control of the heated etching solution.BACKGROUND OF THE INVENTION[0003]In the manufacture of semiconductor devices, acidic etching solutions are used for treating and etching wafers. Phosphoric acid (H3PO4) has bee...

AI Technical Summary

Benefits of technology

This patent describes a method and system for controlling the temperature and hydration of an etching solution used to treat wafers in a process chamber. The method involves circulating the etching solution in a loop and adjusting the hydration and temperature setpoints to ensure the solution is at the desired level for treatment. The system includes a heater, pump, temperature probe, hydration sensor, and water supply for adjusting the solution's water content. The technical effect of this patent is to provide a more precise and consistent etching solution for wafer treatment, resulting in higher quality wafers and improved efficiency of the overall processing process.

Problems solved by technology

When the above boiling point control is applied to a single wafer spin cleaning tool, a new set of challenges arises.

When relatively small changes occur in either the temperature or the hydration level of the phosphoric acid in the circulation loop, the position or region where this boiling occurs can shift within the tool with detrimental effects when processing a wafer with the heated etching solution.

Further, inadequate control of the temperature and hydration level of the heated etching solution can result in poor stability of the etching process, in addition to inadequate etch uniformity across large wafers.

Images